Heat conserver



April 3, 1934. w. D. JOHNSTON HEAT CONSERVER Filed May 25, 1932 1 N V ENTOR. W/7//'0/27 0. Jo/mr/afl n m T T A Patented Apr. 3, 1934 UNITEDSTATES PATENT orF-ica 3 Claims.

This invention relates to improvements in heat conservers and has forits primary object a device adapted to be connected to the flue pipe ofa furnace or stove in such a manner that air 5 passing through pipeslocated therein will be heated by the products of combustion passingtherethrough.

It is a well known fact that a considerable portion of the heat fromfuel is nowbeing wasted by passing directly from the combustion chamberto the flue without performing any useful function, and it is my purposeto extract the major portion of this heat by utilizing it to heat airwhich can then be conducted to a room which is hard to heat.

It happens frequently when a hot air furnace is used that it is almostimpossible to heat-a certain room, and especially a room which requiresa long hot air conduit, because the air therein becomes chilled in itspassage therethrough, that is, its buoyancy is almost entirely lost andit acts as a plug in that conduit and prevents air from the furnace fromentering; consequently, the remainder of the conduits receive more hotair than was intended, but with my device it is possible todeliverfreshly heated air to such conduit at a point removed from'the furnaceand thus restore heat to the chilled air and restore its buoyancy. i

It is also possible with my device to lead the air pipe directly to aroom which is not connected with the furnace and thus heat an additionalroom without installing a larger furnace, and at no increase in fuelcost, since the heat used by 35 my device would otherwise pass into thechimney flue.

My device can also be used to advantage in connection with steam, vaporand hot water plants, as it can be installed in the smoke pipe 40 andthe air pipe be led to a room that it is desired to warm quickly in themorning, since most persons do not maintain the same degree of warmthduring the night as is done during the day, and with the above mentionedheating plants it always takes some time to. get the desired temperaturein the rooms. With my device, however, a selected room can be quicklyheated without the expenditure of any additional fuel.

The device may also be used as a ventilator in cold weather forauditoriums where a steam, vapor or hot water system is used, as the airduct can be arranged to discharge into any. convenient point in .suchauditorium and a constant stream of prewarmed air can be delivered at noadditional fuel cost. In fact, such place can be ventilated cheaper bymy device because the waste heat is used to warm the air before beingadmitted to such auditorium and, consequently, the heating system doesnot have to overcome the lowering of the temperature that follows theadmission of outside air by means of ordinary ventilators. 1 7

My device can alsobe used to advantage with stoves because, by its use,the air in the room will not only be heated by radiation from the stovebut the circulation of air in the room caused by taking air from nearthe floor, passing it through my device where it is heated, and thendischarging it back into the room, will cause an even distribution ofheat throughout the room and the occupants will no longer have to gatherclosely about a stove, in cold weather for warmth, and even thenexperience varying degrees of temperature.

In accomplishing these and other objects of my invention, I haveprovided improved details of structure, the preferred forms of which areillustrated in the accompanying drawing, wherein:

Fig.1 is a perspective view of my device with parts in section, showingthe same located in the smoke pipe of a hot air furnace.

Fig. 2 is an enlarged vertical longitudinal section of my device.

Fig. 3 is a horizontal longitudinal section of the same taken on theline 33, Fig. 2.

Fig. 4 is a cross section of the same taken on the line 4-4, Fig. 3.

Fig. 5 is a perspective view with parts in section of a modified form ofstructure as adapted for use inconnection with heating stoves.

Referring to the drawing in detail:

1 represents a shell or casing preferably cylindrical in cross sectionand having its ends closed by means of heads 2. Each of the heads isprovided with a central opening 3 which is surrounded by an outwardlyextending flange 4 arranged to receive the ends of pipe sections 5 and6, which constitute a part of the smoke pipe of a heating system, thesection 5 being attached, as shown in Fig. 1, to a hot air furnace 7,and the section 6 to the chimney 8. I

The shell 1 has an opening or cut away portion 9 which serves as aclean-out for the removal of soot or dust, and which is normallyclosedby means of a door 10 hinged to the shell along one edge, as indicatedat 11, and which is retained in closed position by means of latches 12.

In the shell are located a plurality of hollo headers 13 preferablytriangular in plan view, and which are provided with circular openings14, 15 and 16, and, as all of these headers are identical, it will beneedless to describe them separately.

Extending upwardly through the shell 1 adjacent one of the heads 2 is apipe 1''] having its end secured in the opening 14 of one of the headers13. Pipes l8 and 19 have their upper ends secured in the openings l5-and 16, respectively, of this header. These pipesextend across theinterior of the shell parallel to the pipe 17, and have their lower endssecured in the corresponding opening of a similar header. A single pipe20, having its lower end secured in the opening 14 of this header,extends upwardly across the shell parallel to the pipes 18 and 19, andhas its upper end secured in the opening 14 of another header lying inthe same horizontal plane as the first mentioned header.

Pipes 21 and 22 have their upper ends secured in the openings 15 and 16,respectively, of the last mentioned header and extend across the shellparallel to the pipe 20, their lower ends being secured in the openings15 and 16 of a header lying in the same horizontal plane as the secondmentioned header, and secured in the opening 14 of this header is a pipe23 extending across and out through the shell and parallel to the pipes21 and 22. The opposite end of the pipe may be connected into any one ofthe hot air ducts or conduits leading from the furnace 7 or it may leadto any desired room, as the necessity requires.

From the foregoing it will be seen that the headers are arranged inpairs lying in the same plane along diametrically opposite sides of theshell with their openings 14, 15 and 16 turned toward each other and theapices of one pair of headers are turned in adirection opposite to thatof the other pair.

Forced air circulation may be obtained by attaching a fan or blower 24to the lower end of the pipe 1'7 and connecting the intake of thisblower to fresh air duct 25, by means of a conduit 26, but if suchforced circulation is not required or desired, the blower can be omittedand the pipe 17 connected directly to the duct 25, in which event mydevice will operate on the thermo-siphon circulation principle.

The passage of air through th described is as follows:

Air enters the pipe 17 and passes upwardly into the first header, thendown through the pipes 18 and 19, into the second header, then upthrough the pipe 20 into the third header, then down through the pipes21 and 22 into the fourth header, and then up through the pipe 23 and tothe point of delivery. During this passage of air, heat is absorbed fromthe flue gases which pass from the combustion chamber through the pipe 5into the shell, where they completely surround the headers and pipestherein, and then these gases, now having a greatly reduced temperature,pass on to the chimney 8 through the pipe 6.

From the foregoing it will be seen that-I obtain a continuous supply ofheated air which can be delivered at any required point without theexpenditure of additional fuel.

After the device has been in operation for a period of time the door 10maybe opened and the accumulated soot'or other solidmatter, carried bythe flue gases from the combustion chamber and deposited in the shell,can be removed, the opening 9 being of such size that all parts thereinare readily accessible. The heat conserver just described may be termedthe horizontal type and structure just instance the headers are arrangedin pairs parallel to the heads 28 and 29 instead of parallel to theshell, as shown in Figs. 1, 2 and 3.

The head 29 isprovided wih an opening through which a pipe 33 extendsvertically, and which has its upper end secured in a header 32 adjacentthe head 28; secured in this header are the upper ends of pipes 34 and35, which are parallel to the pipe 33 and which have their lower endssecured in a second header which is located adjacent the head 29. A pipe36, having its lower end secured in the last mentioned header, extendsupwardly parallel to the pipes 34 and 35 and has its upper end securedin a third header adjacent the head 28. Pipes 37 and 38, having theirupper ends secured in the last mentioned header, extend parallel to thepipe 36 and have their lower ends secured in a fourth header which isadjacent the head 29. A pipe 39, having its lower end secured to saidlast mentioned header, extends upwardly parallel to the pipes 37 and 38.The pipe 39, however, is of less length than the pipes 37 and. 38, andhas an elbow 40 on its upper end from which a pipe 41 extendshorizontally through the shell and discharges heated air into the room.

The lower end of the pipe 33 terminates near the floor of the room sothat the coldest air in the room will be drawn therein, and if desired ablower may be attached thereto. The pipe 41 may also be extended so thatthe air will be discharged into another room or at a point remote fromthe shell.

From the foregoing it will be noted that the headers are connectedtogether in opposing pairs by means of pipes, and a header of one paircarries an inlet pipe and a header of another pair carries an outletpipe, so that the air in passing from the inlet pipe to the outlet pipemust follow a sinuous course through a heated zone.

It will also be noted that the air entering the first header passesthrough a single pipe. The air becoming warmed expands in the header,and, on account of the double connection to the second header and theconsequent larger passage aiTorded, the air moves down into the secondheader, and, during its passage to and while in the second headerbecomes further heated, causing more expansion. As the air leaves thesecond header it passes upwardly to the third header through a singlepipe where its natural tendency, to rise in addition to the expansion,causes it to flow at an increased rate of speed. The same is repeated asthe air passes from the third to the fourth headers and out through thepipe 23, and this intermittent acceleration of the air column as itpasses through my device seems to create an action similar to airpassing through a venturi' by increasing the natural rate of flow of theair column, and, consequently, I am enabled to heat'a greater volume ofair in a given length of time when usingthe thermo-siphon system of aircirculation than can be where the buoyancy of heated air alone is reliedon. In

other words, I have a heat absorbing coil having alternate or spacedapart portions which automatically increases the rate of flow of airtherethrough as it is being heated.

What I claim and desire to secure by Letters Patent is:

1. A heat conserver comprising a shell having a head at each end adaptedto receive a pipe section, a plurality of headers located in said shell,pipes for connecting said headers together in opposing pairs, an airinlet connected to one of said headers and extending beyond said shell,an air outlet pipe connected to another of said headers and projectingbeyond said shell, and means connected to the projecting end of said airinlet pipe for delivering air to said pipe and passing the same throughsaid headers and the pipes connected thereto.

2. A heat conserver comprising a shell having a head at each end adaptedto receive a pipe section, a plurality of headers located in said shell,pairs of pipes for connecting selected headers together in opposingpairs, a single pipe for connecting a selected header of each pairtogether, thereby forming a heat absorbing coil having a header at eachend, an air inlet pipe connected to one of said end headers andprojecting beyond said shell, and an air outlet pipe connected to theremaining end header and projecting beyond said shell.

3. A heat conserver comprising a casing having inlet and outletconnections for passage of a heating medium therethrough, a plurality ofheaders located in the casing and spaced from the walls thereof, pairsof pipes for connecting selected headers together in opposing pairs, asingle pipe connecting a selected header of each pair together therebyforming a heat absorbing coil completely surrounded by the heatingmedium in the casing and having a header at each end, an air inlet pipeconnected to one of the headers, and an air outlet pipe connected to theremaining header.

WILLIAM D. JOHNSTON.

